Abstract: A music or audio composition system, or other composition system for time-based media such as video, defines a composition using a set of tracks. Similar to a traditional track, each track in the composition system is represented in a graphical user interface as a timeline. However, each track also has its own attributes that are used to access a content database. As a result, each track may have its own context-sensitive browser or other mechanism to access the content database. The attributes of a track may include, for example, an associated instrument category, musical style and qualifying parameters. In the graphical user interface, if a user selects a track and inputs search parameters for browsing the database, the results from the database are limited to those that also match the attributes of the track in addition to the user-provided search parameters. For example, the browser for a drum track will provide drum clips; the browser for a bass track will provide bass clips.